A test of the instanton vacuum chiral quark model with axial anomaly lowenergy theorems
Abstract
The QCD+QED axial anomaly lowenergy theorems are applied to estimate the accuracy of an instanton vacuum  based chiral quark model. The lowenergy theorems give an exact relation between the matrix elements of the gluon and photon parts of the QCD+QED axial anomaly operator equation. The matrix elements between vacuum and two photon states and between vacuum and two gluon states are calculated for arbitrary N_{f}. It is shown that this model does satisfy the lowenergy theorems with an accuracy of ~ 17%. We estimate also the contribution of the nonperturbative conversion of gluons into photons to the decay η' > 2γ and compare with experimental data.
 Publication:

Physics Letters B
 Pub Date:
 February 1997
 DOI:
 10.1016/S03702693(97)00052X
 arXiv:
 arXiv:hepph/9610418
 Bibcode:
 1997PhLB..395..298M
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
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